1. Field of the Invention
The present invention relates in general to switches and circuits incorporating the same, which operate through interaction of elementary particles, including electrons and photons, for example.
2. Description of the Background Art
The transistor was a huge breakthrough in the electronics industry when it was introduced some 40 years ago, and even today, continues to serve as the basic circuit element in all high speed computing devices, for example. However, as the demand for faster and faster computers increases, researchers continue to look for more efficient, higher speed switching devices. The transistor, even in its modern high tech forms, such as the variations on the FET, is still inherently limited by its fundamental theory of operation which relies upon the flow of electrons.
This has led to development of alternative forms of switches and devices that rely upon the particle theory of quantum mechanics for their operation in which interaction of elementary particles, such as electrons, photons and protons, is used to transfer information. These quantum devices are smaller than conventional FETs by several orders of magnitude and operate with minimal, quantum scale power input. However, up to now, quantum devices, such as quantum computers are intended to operate in a massively parallel manner in which the states of many particles known as qubits are used to transmit or store information, for example. As a result, the devices suffer from signal-to-noise ratio limitations and decoherence. More particularly, since information is contained in a large number of particles in parallel, corruption of even one particle""s information can result in total loss of all the information. Further, these known devices work by setting and sensing the various states of the particles, such as electron spin direction, polarization, etc., which further exacerbates signal detection.
The present invention overcomes the drawbacks of previous quantum computing devices and logic circuits through provision of quantum switches and devices which operate on the basis of sequential, single particle interactions, thereby avoiding the decoherence problems assisted with multi particle, parallel systems. In its simplest form, the invention comprises a quantum switch referred to as a trisistor, which operates in a manner similar to that of a conventional transistor in which a control input determines the value of an output. However, unlike a conventional transistor, which relies on the flow of electric current for operation, the trisistor operates in response to interactions between pairs of elementary particles. More particularly, a first elementary particle (EP), such as a photon or an electron, is used as a control input to the trisistor and interacts with a second EP, thereby inducing a detectable state change in the second EP that determines the trisistor""s output value. The physical property which determines the particular EP state could be, for example, polarization, spin direction or energy level, and would be binary in the simplest embodiment. In another embodiment, the state values could have more than two values. A good example would be the energy levels of an electron in an atom where many states are available.
In some embodiments of the invention, switches and circuits can be constructed that do not require setting or detection of specific particle state values, but instead, operate through control of a state of one particle relative to the state of another particle. For example, in one embodiment of the invention, a pair of photons is generated in response to an electron state change which can be set to have either the same or different photon polarizations. The actual polarization of the particles need not be known nor measured; instead, the device need only know whether the polarizations are the same or different.
The operation of the various embodiments of the invention is based on a triadic theory of particle behavior that the inventors have proposed. The inventors have given this theory and the method derived therefrom the name Peirce-Beil-Ketner (PBK). Under the novel point of view and application of the PBK method all interactions between elementary particles can be defined as a function of a history of each particle""s quantum states both before and after the interaction between the two particles. The history of an EP as it interacts with other particles can therefore be defined graphically by a plurality of interconnected three legged diagrams, known as triads. Each triad represents the interaction of the EP with another EP. A first leg of the triad represents a quantum state of the particle before the interaction, a second leg is connected to the corresponding leg of the interacting particle and represents the interaction itself, and a third leg of the triad represents a quantum state of the particle after the interaction. Each triad thus forms what can be referred to as a quantum switch that behaves much like a conventional transistor by providing a variable output that is a function of an input particle""s quantum state and the interaction. The inventors refer to this device as a trisistor since it can provide the same function as a transistor, but operates in accordance with their triadic particle theory and the PBK method.
Just as conventional transistors can be grouped together to form logic or computer circuits, the EP-based trisistors using the PBK method can be combined to form various types of logic gates, circuits and other computer circuits. A significant advantage of these circuits over previous quantum mechanics based computing circuits is that the subject circuits comprise a plurality of trisistors that operate in series with one another, thus eliminating the signal decoherence problem associated with previous multiple particle state, parallel devices.
To implement the trisistors, one preferred embodiment employs a thin section of nonlinear crystal, such as beta barium borate. In this embodiment, the device operates based on the control and detection of polarization states of elementary particles, in this case photons, emitted by the crystal. More particularly, in one operational embodiment, a UV photon is used as input in the device and is incident on the crystal at a controllable angle. The angle of incidence, which is controlled using conventional beam handling devices, such as mirrors or lenses, determines the output of the trisistor in the following manner. As the incoming photon impinges on the crystal, it interacts with an atomic electron in the crystal, thereby changing one of its states, in this case, its energy level. If the angle of incidence is properly selected, two IR photons will be emitted by the crystal as a result of a decrease in the electron""s energy level. The operation of the crystal as a trisistor in all configurations is thus the interaction of incoming and/or outgoing photons with the atomic electrons of the crystal. In general, the dipole moments of the atoms interact with the polarization vectors of the photons. Depending upon the angle of incidence of the incoming UV photon on the crystal, two IR photons will be emitted by the crystal having either different or the same polarizations, a condition that can be readily prepared and subsequently detected without actually determining the polarizations of the IR photons.
The trisistors can be configured in various, complementary manners so that the devices can be combined together in series to form various types of logic gates or circuits. For example, a second embodiment of the trisistor operates in the inverse manner to generate an output UV photon if two incoming IR photons, which are highly correlated, are simultaneously incident on the nonlinear crystal. Thus, by combining this trisistor with the previously discussed trisistor, a logic gate function can be realized if one or more additional trisistors are employed to alter the polarization of one of the IR photons after it is generated by the first trisistor, but before it is detected by the second trisistor.